Sleeping bag and heater therefor



Feb. 11, 1969 R. J. COSTANZO `'3,427,431 l SLEEPING BAG AND HEATER THEREFOR 'Filed Deo. 15, 196e FIG. l

INVENTOR. Raphael AJoseph Costanzo T TO RNEY United States Patent Oliice 3,427,431 Patented Feb. 11, 1969 4 Claims ABSTRACT F THE DISCLOSURE This disclosure is directed to an electrically heated sleeping bag and an improved low-voltage electrical heating means adapted for use therewith. 1n one form of the disclosure the heating means comprises a resistor element having a radiation surface connected thereto in electrically insulated, heat transferable, relationship to provide for a maximum of heat transfer with a minimum of voltage input to the resistor. A source of low-voltage electrical energy is connected in circuit with the resistor element, the source of energy being carried in a pouch which is constructed so as to be readily detachably connected to the sleeping bag.

Object of the invention An object of this invention resides in the provision of an electrically heated sleeping bag having a heating element which is constructed 'and arranged so as to be energized by a very low source of electrical energy.

It is another object of this invention to provide a sleeping bag with an electric heater having self-contained power source which can be readily detachably connected to the sleeping bag.

Another object of this invention is to provide an improved low-voltage electrical heater having a radiation surface connected in heat transfer relationship to the resistor element thereof.

Another object of this invention is to provide an improved electrical heater which is durable in construction, inexpensive to manufacture and positive in operation.

Another object of this invention is to provide an improved heating element capable of transmitting heat over a considerable area with voltage input thereto.

Brief description of the invention The foregoing objects and other features and advantages of this invention are attained by a sleeping bag defined by an upper portion and a bottom portion which are suitably connected about the peripheral or marginal edge thereof to define a bag-like configuration into which a person may comfortably lie. The sleeping bag is rendered electrically heated by a very low-voltage electric heater imbedded in a portion of the sleeping bag. The electric heater comprises a strip of bare resistor connected in circuit with a low-voltage source of electrical energy, e.g., a battery. A heat radiation surface is connected directly to the bare resistor as to be electrically insulated in heat transfer relationship therewith. In this manner the heat transfer area of the heater is substantially enlarged, thereby enabling maximum heat transfer with a minimum amount of voltage input to the resistor. Connected in circuit with the heater is a battery source of electrical energy. Preferably the battery is carried in a pouch which is adapted to be detachably connected in circuit with the heater from an exterior portion of the sleeping bag. Also a switch means is provided for making `and breaking the circuit to the resistor element without effecting removal of the battery pouch. If desired, a circuit breaker is interconnected in series between the source of power and the heater 4for making and breaking of the `circuit in accordance with predetermined temperature conditions.

A feature of this invention resides in an electrically heated sleeping bag which is relatively inexpensive to fabricate and which is positive in operation.

Another feature of this invention is to provide a sleeping bag which can be effectively heated electrically by utilizing la self-contained source of low-voltage electrical energy.

Another feature of this invention resides in the provision wherein the sleeping bag may be optionally utilized either as a conventional sleeping bag and/ or as an electrically heated sleeping bag.

Another feature of this invention resides in the provision wherein the source of electrical energy can be readily detachably connected into electrical circuit with an electrical heater of the bag.

Other features and advantages will become more readily apparent when considered in view of the drawings and specification in which:

FIG. 1 is a perspective view of a sleeping bag embodying the present invention.

FIG. 2 is an enlarged detailed sectional view taken along lines 2--2 on FIG. 1.

FIG. 3 is a schematic diagram of the electrical circuit for energizing the heater. Y

FIG. 4 is a perspective view illustrating the pouch or carrier for the source of electrical energy.

FIG. 5 illustrates a sectional view of the battery pouch of FIG. 4.

b FIG. 6 is an enlarged detail of a portion of the sleeping Referring -to the drawings, there is shown in FIG. 1 a sleeping bag 10 comprising essentially of an upper blanket or portion 11 :and a lower blanket or portion 12 which may be suitably connected along the peripheral edges thereof as by seam 13 to define a bag-like formation in which one may lie. The respective upper and lower blankets 11 and 12 are preferably simil-arly constructed. As shown in FIG. 2 the blanket portions comprise an inner and outer lining 14 and 15 respectively. To increase the warmth of the sleeping bag 10, there -is provided an electric heating means 16 which is specifically constructed and arranged so as to be energized by a very low-voltage source 17 of electrical energy, as for example a battery of six Volts or less.

As is best seen in FIGS. 2 and 3, the electrical heating means of the invention comprises an elongated bare fiat 4resistor element 1-8, as for example Nichrome of a suitable length, positioned between the upper and lower liner portions 14 and 15 of the sleeping bag blanket 11. While the heating element is illustrated as being interposed in the upper blanket 11 of the sleeping bag, it will be readily appreciated and understood that the heating element may -be interposed either in the upper and/or lower heating blanket 11 or 12 of the sleeping bag, as may be desired and/for located along any desired portion thereof.

Referring to FIGS. 2 and 3, the heating area of the resistor element 18 is expanded by utilizing a heat radiation surface 19 connected in heat transfer relationship with respect to the resistor element 18. The heat radiation surface 19 may comprise any suitable metallic sheet material or foil, as for example sheet aluminum or aluminum foil and the like, secured in heat transfer relationship to the resistor element. Accordingly, the back of the metallic foil 19 may be coated with a suitable dielectric adhesive which will effectively electrically insulate the radiation surface 19 from the resistor element while at the same time secure the radiation surface 19 into good thermal conductivity with the resistor element 18. As best seen in FIG. 2, a resistor element 18 is sandwiched between an upper and lower sheet of metallic foil 19, 19 which sheets 19-19 are disposed in back-toback relationship. Accordingly, it will be noted that the radiation surface 19-19 provides an expanded heating surface connected in thermal heat transfer relationship with the resistor element 18. If desired, the radiation surface or metallic foil 19 may be also electrically insulated from the resistor material by anodizing the back surface of the foil which is adapted to contact the resistor element 18.

The resistor element 18 is suitably connected in circuit with the power source 17 by electrical wires or conductors 20 and 21. A suitably switching means 22 is interposed in the circuit for making and breaking the circuit to the resistor element 18. Also, if desired, a circuit breaker 23 may be disposed in series between the source of electrical energy 17 and the heating means 16 which will automatically make or break the circuit according to temperature generated by the heater 16.

As best seen in FIG. 1, the free ends of the conductors 20, 21 are electrically connected to a terminal or contacts 24 and 25 comprising, c g., a male snap fastener.

The construction of the heater 16 is such that it can be effectively energized for considerable periods of time by a source of very low-voltage electrical energy, such as battery 17. Referring to FIG. 5, two low-voltage batteries are connected in series to generate the voltage requirement for energizing the heater 16. Small alkalinetype batteries have proven to be most satisfactory. A pouch 26 is provided for detachably connecting the batteries 17 to the heating blanket. By rendering the source of electrical energy 17 detachably connected to the sleeping bag 10, the sleeping bag 10 can be then optionally utilized either as a conventional sleeping bag or as an electrically heated sleeping bag.

To detachably connect the source of electrical power to the sleeping bag, the pouch 26 is provided with snap fasteners 27, 28, 28A which connect and disconnect with complementary male snap fasteners 24, 25, A.

Referring to FIGS. 4 and 5, it will be noted that the pouch 26 comprises a bottom wall 26A having connected thereto a circumscribing upright Wall 26B to define a substantially rectangular open end pouch. The pouch 26 may be formed of any suitable material, such as plastic or the like. As shown in FIG. 5, a plate contact 30 is resiliently supported on the bottom wall 26A of the pouch vby a layer of resilient material 31 such as foam rubber, sponge, or the like. An envelope 32 formed of relatively rigid material,` s for example paperboard, hardboard, or the like, is isposed within the pouch 26 to add rigidity thereto and to shape the same. Connected to the back wall of the pouch formed integrally therewith is a flap 33 which is adapted to define the closure for the open end of the pouch 26. A pair of contact buttons 34, 35 are connected to a portion of the iiap to effect engagement with the respective electrodes of the batteries 17 when the liap 33 is closed. On the back of the pouch are provided a pair of complementary female snap fasteners 28, 28A which are adapted to mate with the male fasteners 25 and 25A connected to the bag 10 to support the pouch on the bag 10. One of the snap fasteners 28 on the back of the pouch 26 is suitably wired by conductor 36 to one of the contacts 34 on the Hap portion 33 of the pouch. The other contact bottom 35 on the flap portion 33 of the pouch is suitably wired by conductor 37 to a contact fastener 27 carried on a tab 38 extending laterally of the pouch. Accordingly, it will be noted that the pouch 26 is provided with three snap fasteners 27, 28, 28A, of which two define the electrical terminals 27, 28 which are adapted to mate with the complementary terminal fasteners 24 and 25 on the sleeping blanket. Accordingly, with the construction described, it will therefore be apparent that the contact fastener 24 and contact fastener 27 carried on tab 38 function as an on-off switch for the heater means 16 of the sleeping bag.

In operation, the pouch 26 is detachably secured to the 'sleeping bag by engagement of complementary fasteners 25, 25A, and 28, 28A whereby the heater 16 will not be energized until complementary contact fasteners 24 and 27 have been closed or fastened. Thus, the occupant of the bag can effect control over the electrical heater 16 merely by snapping or unsnapping the complementary contacts 24 and 27 without effecting complete detachment of the pouch and batteries therein from the bag.

While the instant invention has been described with respect to several embodiments thereof, it will be readily appreciated and understood that variations and modifications may be made without departing from the spirit or scope of the invention.

What is claimed is:

1. A sleeping bag comprising an upper portion .and a lower portion,

means for connecting said upper and lower portions about the peripheral edges thereof to define a baglike form opened at one end and sized to receive the body of a person,

and means for electrically heating said bag,

said latter means comprising .a flat bare electrical resistor element to impart heat to said bag,

imeans for radiating the heat generated by said resistor element,

said radiating means including a sheet of heat-conducting material connected to the opposed at sides of said resistor element in direct heat transfer relationship to sandwich said resistor element therebetween,

means for adhesively securing said heat conducting sheets in back-to-back relationship to sandwich said resistor therebetween,

said heat conducting sheets each having a surface area greater than the surface area of the resistor element sandwiches therebetween to define an expanded surface area,

a low voltage battery defining the source of electrical energy connected in circuit with said resistor element,

and means for detachably connecting said battery into electrical circuit with said resistor.

2. The invention as defined in claim 1 including:

a pair of electrical conductors connected in circuit with the resistor,

a pair of snap fasteners connected to the free end of said conductors to define a terminal therefor,

and said means for detachably connecting said energy source including `a pouch for supporting a battery therein,

a bottom Contact located on the bottom of said pouch,

means for resiliently supporting said bottom contact,

a flap connected to said pouch to form a closure therefor,

a contact connected to said flap to make electrical contact with the electrode of the battery,

a pair of complementary snap fasteners contacts connected to said pouch for detacha'bly connecting said pouch to the terminal contacts of said conductors to effect the circuit between the battery and the resistor,

and a circuit breaker connected in series with said resistor.

3. An electrical heater construction comprising,

a substantially flat bare electrical resistor element consisting of a relatively long narrow strip of electrical resistant material,

a radiation means including a thin sheet of heat conducting material connected to the opposed flat surfaces of said resistance element to sandwich said element therebetween,

said heat conducting sheets being connected in direct heat transfer relationship to said element,

means for adhesively securing said heat conducting sheets in back-to-back relationship to sandwich said resistance element therebetween,

said heat conducting sheets each having a surface area 5 6 greater than that of the at surfaces of said resistance 2,456,468 12/ 1948 Theodore 219--212 element, 2,5 84,302 2/ 1952 Stein 219-527 a source of low voltage electrical energy for energizing 2,697,775 12/ 1954 Licht 2l9212 said resistance element, 2,845,519 7/ 1958 Wllat 219-528 said source of electrical energy including a every 10W r 1,996,522 4/ 1935 Norris 219-528 voltage battery, o 2,889,445 6/ 1959 Wolf 219-530 X means for supporting and connecting said battery into 2,993,979 7/ 1961 Hornsby 219-212 electric circuit with said resistance element, 3,084,424 4/ 1963 Carrona 219-211 and said latter means including a length of insulated 3,293,405 12/ 1966 Costanzo 219-211 conducting Wire for electrically connecting said 10W 10 3,334,363 8/ 1967 Lutz 5-343 voltage battery in circuit with said resistance element. 4. The invention as defined in claim 3 wherein said FOREIGN PATENTS radiation means includes a sheet of metallic foil disposed 765,709 1/1957 Great Britain in back-to-back relationship to sandwich therebetween said electrical resistance element in direct heat transfer l5 VOLODYMYR Y M AYEWSKY, prima,y Examnen relationship thereto.

References Cited U,.S.C1.X1R. UNITED STATES PATENTS 21a-211, 528, 544; 5-343, 347 750,179 1/1904 Foglesong 219-212 20 

